BAC Calculator – Blood Alcohol Content Estimate

Estimate blood alcohol content based on drinks, weight, sex, and time elapsed.

❤️ Health📐
Weight (lbs)
Standard drinks consumed
Hours since first drink
Sex
Please enter valid values.

Formula & Reference

VariableFormulaUnits
BAC Calculator – Blood Alcohol Content Estimateresult

Step-by-Step Examples

Example 1
160lb male, 3 drinks, 2hrs

  • BAC: ~0.064% — below 0.08% but impaired, do not drive
✓ 0.064%
Example 2
130lb female, 2 drinks, 1hr

  • BAC: ~0.066% — close to legal limit!
✓ 0.066%
Example 3
5 drinks, 3hrs

  • Likely over 0.08% limit — arrange a ride
✓ Likely over limit

Real-World Applications

Common Mistakes to Avoid

⚠️
This is an estimate

Actual BAC varies with food, metabolism, medications.

⚠️
Feeling sober is not safe

Impairment starts well below 0.08%.

Frequently Asked Questions

US legal limit?
0.08% for drivers 21+. Commercial: 0.04%. Under 21: 0.00-0.02%.
How long to sober up?
~0.015% per hour. Nothing speeds this up.
Standard drink?
1.5oz spirits, 5oz wine, or 12oz beer = one standard drink.

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